Process of treating ores.



PATBNTED DEC. 13. 190s 3.1?.GPMELQAVVAVLT.` y1 PROCESS QP TR'EATING om. ^LmTIN-PFER M3121, 190s. nnnnwnn un, a4, 190e.

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UNITED srAriis' rarriivr onirica;

JOHNLE. GREENAWALT, or iiENvER, COLORADO;-

1 PRoCEssoF TBEATINGQRES.

Specification of Letters Patent. l

lPatentedvDec.v 18, 1906.

applicati@ iisd Marci 2 7, 1905-.. aeiiewei April 24. 1906. serial No. 313.402.

To all whom it may concern: f I

- Be it known that I, JOHN E. GREENAWALT,

a citizen'o'f the United States, residing in the cit and county of Denver and State of Colora 0,'have invented a certain new and useful Process of Treatin Ore and other Material; and I do declare t e following to be agfull, clear, and exact descriptionof the invention, such as will enable others skilled in the art to which it appertains ,to make and use the same, reference being had to the accompanying drawings, and to the letters and figures of re e rence marked thereon, whichiform a part of thisspecification.

My invention relates to a process of treating ore or other materialand, broadly stated, involvesv the placing of the material toy be treated upon a porous bed, heating the material, and through the material and through the'porous v bed forming the support for the material.

It also involves the introduction of air or' other gas above the porous bed and the material thereon, the said air or gas being introduced at a distance from a source of heat.

It furthermore involves the passage of the air or other gas or fumes down through`thev 1 material andthe porous bed, through the instrumentality of suction acting from below,

and,finally, the invention embraces the conf densation ofthe fumes or gasesipassedfdown wardly through the porous bed,

whereby their values are recovered.

In carrying out or practicing my im roved I process I prefer to utilize a porousearth roasting-furnace of the type set forth in my a plication led December 27, 1.90.1', Serial o. 87,510. An im ortant improvement over the process descr ed in my said original 4application lies in the fact that by virtue of' my improved process I am able to recoverl any. va ,and therefore mingle with the fumesv arising ues which have become volatilized,

from the `material under treatment within the furnace; By virtue of the old' process, or that set forthfin'niy original application, no provision was madefor recovering the values of these fumes, since the air orother gas employed in the treatment of the material'upon .they porous lhearth `was passed through the' hearth and through the materi l fromhelow.

' Consequently the volatilized values mingling with the fumes would naturally pass out ofthe furnace and 'into the stack with the'v waste .gases or products of combustion; In my improved process the necessaryy air or other gas passing air or other gas down` y'for supporting combustion within the furnace may be introduced to the roastingchamber from the top of the furnace and delivered to the roasting or oxidizing chamber above the porous hearth and above the bed of material under treatment thereon, the said air ,being introduced at a distance'from the source of heat or the oint where the producer-gas employed is c elivered to the roasting-chamber. By virtue of my improved process I not only recover the precious-metal values contained in the fumes, butiI am also ufacture ofsulfuric acid. There are certain ores carrying the precious metals insuch combinations that when able to treat the sulfurous fumes for the manthe .ore is roasted a considerable `percentage of the gold `and silver yvolatilizes in the form of fumes, and inthe Ordinar furnace these valuable fumes mixwith tie products of` combustionv and dust of the furnace and pass vinto dust-chaiiibcrsl and the furnace-stack.

Experience v'has vshown that it is a difficult matter tocom letely precipitate and recover these values a ter they are mixed or min led with the large volume of ,fuel-gases and ust l arising from the ore or other material under treatment. In `my invention, b reason of a downward suction vthrough thel earth, these fumes arev drawn downwardly lthrough the lhearth and deposited in a'condensing-chamber in a comparatively urestate. By this ,arrangement the valuab e constituents of the gases are concentrated in a small current as compared with the total volume vof fumesgases 'above the bed the oxidation andl heating'of the ore can be greatly and economically romoted. Again., by incorporating a suita Ale catalytic agent-such as platinized asbestos, '.ferric oxid, &c.-in the porous bed a' considerable proportion ofthe sul- Y furous anhydrid can be cheaply and economically converted into sulfuric anhydrid, and thus into sulfuric4 acid, inthe .condensingchamber. i 'l f Suitable mechanism for practicing my irnproved process willwnow` be described, refer-l Figure 1 is'a cross-section of the furnace, the condensing-chamber being shown. invertical section. Fig. 2 is a top plan view of the furnace shown on a smaller scale, the flues for the introduction ofthe heat or fuel gases at one end of the furnace and for the escape of the waste gases at the opposite extremity ofthe furnace-being shown in horizontal section. Fig. 3 isa central longit dinal section taken throughthe furnace on t 'e same scale a's-Fig. 2.

Thesame reference characters indicate the sameparts-in all the views.

Wlenroreis roasted u cna orous-bed of thecharacter illustrate in t e drawings, rabbling mechanism isnecessary for the urpose of. stirring the-ore-and advancing'it ongitudmally' on the hearth, whereby new suraces ofthe ore-are constantly exposed-to the action of the-heat. Inthe furnace illustrated in the drawings I contem late the use ofrabbling mechamsnnas will e readily observed from an inspection thereof. themselves, however, are not illustrated; but it must beunderstood that their employment will'berequired; `To-thisend- I have shown sprocket-wheels-20 at each endof the furnace, whichE the endless rabble-chains (not shown) would' engage vin actual practice. InA these drawings'the ore to be roasted orvtrea'ted is ence beingnmade to the accompanying draw# ings, in w lsupposed-to be'placed-upon-the orous bedl 11.

'llhisbed constltutes vthe heart -of the furnace, andthe ore is rabbledtover-this hearth bjr-suitable mechanicalrabbles. `(Not'shown, but. heretofore briefly described.) The fur- -naceis-heated by means of producer-gas in.l

troduced throu hy the flue v2 and is su plied at intervals-wit -air through aseries olP pipes 3`,.having nozzles passing through the top cf the-furnace, enou h ipes and nozzles being employedto givet e esired-'or'necessary dis* tributicn, the air being suppliedtothe pipes S'rom a main pipe t3, connected with any suitable source oi'air-su ply. The ain so introducedmingles with t eprcducergas, furnishin the necessary heat for the roasting operatlon, and? the waste gases pass throu h t 'e-i'ue 4 to the chimney or stack. Direct Iy underneath the porous hearth or bed are large chambers w andb, which are dividedfby suitable cross-walls intocompartments, so that the volume of gases drawn through the hearth may be concentrated and regulated in@ the different compartments. The hearth is constructed upon a series cf arches in the forms of solid rings 5, having spaces C of about four' inches in width betweenthem. These s aces are covered by a course of bricks Il apart, leaving intermediate s aces E cemmunicating with the -spaces between. the anches.. 5. Upon-'these bricks is placed a layer ofocarse gravel or ore F and .thena The rabbles set on edge and about one inch.

layer of smaller pieces until the last four inches, which consist ofsand or fine ore.

The gases are drawn throu h the ore-bed in thebottom of each chamber, the saidv reservoirs being suppliedv with lwater from perforated pipes 10, mountedf in the to of ther condensing-chamber. Thecondense orprecipitated values may be easily recoveredffrom Lthe reservoirs 19. Y Having thus describedvmy invention, what I claim is- .A

1. The herein-describedprocess of treating ore or other material, consisting in placing the materialupon a porous bed, subjecting the same to heat and passing a portion of the resulting fumes or gases, down through the porous-bed. l

2. The herein-described fume-recovery process, consisting'in placingthe fumero- -ducing material as-ore'u on a porousl ed, subjecting the same to. eat, pass' ,the fumes or a portion thereof down throng the bed, and finally precipitating the fumes so passed through the be 3. The' herein-describedprocess'ofrecovenf i ing valuesl from the fumes ior gases-.arising while roasting ore, consist/ing in placmgthe ore upon a porous-bed, subjectingthe same to heat, and passing the resultln yfumes, or'a portion thereof down through t e bed.

4. Aprocess of recoverin values fromthe fumes arising fromore whi e roasting, con- IIO sisting in placing theoreupon a porous bed,

subjecting the same to heat, passing theresulting fumes or aV portion` thereof down through the bed, and finally condensing the .fumes 5. An ore-treating process consisting in placing the ore upona porous bed, subjecting the same to heat, and passing the resulting fumes or a portion thereof down through the bed by suction acting from beneaththe bed.

6. The herein-described ore-treating process, consistingin placing a bed ofi ore upon a porous hearth, containinga catalytic agent, subjecting the ore to-heat, and passin the resulting fumes or aportion thereof. own throughthe orebed and through the' porous hearth'.

' 7. A process oftreating ore, consisting 1n placing a bed of oreupon a porous-hearth, containing a catalyticv agent, subjectmg'the r 5 layer'of the material upon a porous `ore to'heat, passing thev "resulting gases or a portion thereof down through "the ore-bedv and through the porous hearth, and finally condensing the fumes or gases.

5 8. An oretreating process consisting in placing a bed ofy ore upon a porous hearth,

containing a catalytic agent, subjecting ,the

jecting the material to heat, and passing .air

or other ases down through the layer of material and through the porous bed.

10. The herein-described process of treat- 2o ing ore o'r other material consisting in placing a layeriof the material upon a 4porous bed, subjecting the same .to,heat, introducin air or other gas above the bed at a distance om l the source of heat or fuel-supply, arfid passimy ayer o l materia i 5 y theair. downthroug'h the and through the porous bed.

11. The herein-described ore roasting or 'foxidi'zing process, consistin of lacin a bed il p g of'l ore upon a porous heart subjectmg the -sarne to heat, introducing air or othergas 3o above the bed at a distance from the source of heat or fuel-supply, and passing the air or other as -down through the ore-bed and throug the porous hearth. p l y In testimony whereof I affix my signature 3 5 in presence of two Witnesses. l

JOHN E.. GREENAWALT.

Witnesses:

. DENA NELSON, I

A. J. OBBIEN. 

